In a move which has echoes of the EU’s plan to exclude Britain from theGalileosatellite system, Mr Barnier said there would be “difficult negotiations” over the maintenance of access to parts of the EU’s database. A diplomatic note circulated to ambassadors of the remaining EU27 states, whom Brexit negotiator Mr Barnier met on Friday, paid tribute to UK Prime Minister Theresa May for sticking to the agreed withdrawal agreement despite fearsome domestic opposition which could see her face a no-confidence vote as Tory Party leader in the next few days. But he rejected the idea of the UK having access to the EU’s internal security system, including its passenger name recognition database, Europol and Eurojust, the Financial Times reported. According to the note, Mr Barnier said: “The UK does not accept all the consequences of its status as a third country.”

No other country outside the Schengen free travel area was able to access the system, he explained.

Mr Barnier was meeting representative from the EU27 for the first time since the agreement of the terms of the divorce deal.

The 565-page draft withdrawal agreement, which was published on Wednesday, outlines the UK’s relationship with the EU after it leaves the bloc on March 29, 2019.

The text leaves the questions of UK’s co-operation inEuropol, the EU’s law enforcement agency, and Eurojust, its legal agency, open to negotiation.

However, Mr Barnier told ambassadors access to security databases was one of the two “serious problems”, alongside the UK’s bid to maintain frictionless trade in goods, which had emerged over the course of talks between EU and UK negotiators leading up to the publication of the document.

It is not the first time Mr Barnier has adopted an uncompromising stance on security issues – in June he told diplomats in Vienna Britain would be “outside the EU’s legal order”, adding: “This is a fact – facts have consequences.”

He said the EU would “cooperate strongly” with the UK to fight terrorism, cyberattacks and radicalisation.

However, he also called he called for “more realism” from Britain in terms of what degree of police and judicial cooperation would be possible after Brexit.

At the time, Anna Nadibaidze, a researcher with the Open Europe think-tank, told Express.co.uk Mr Barnier’s insistence that Britain will be excluded from the European Arrest Warrant system after the UK leaves the bloc will pose security risks for both sides.

The European Arrest Warrant (EAW) permits another EU member state to arrest and transfer a criminal suspect or sentenced person to the issuing state in order that they can be put on trial or complete a detention period.

If Britain is no longer included, this process is likely to be significantly complicated, a possibility Mrs May is known to be unhappy about.

Ms Nadibaidze said: “The EU has set a strict position on security and justice and home affairs cooperation after Brexit, which it justifies by referring to the UK’s ‘red lines’, such as the Government’s position the jurisdiction of the European Court of Justice (ECJ).

“It looks like the Commission has decided to take advantage of the UK’s domestic focus on the ‘meaningful vote’ and splits within the Conservative Party to set out its own ‘red lines’, and put pressure on Theresa May to make concessions.”

During his speech, Mr Barnier had implied that after Brexit, extradition will be based on the 1957 Council of Europe European Convention, which is not part of EU institutions, but which all EU member states have signed and ratified.

She added: “If this will be the case, the procedure of surrendering criminals between the UK and the EU is highly likely to be more complicated, create significant delays (possibly months instead of days) and involve more costs for authorities on both sides.”

Mr Barnier has also indicated Britain will not enjoy full access to Galileo after leaving the bloc – despite having played a major role in developing the technology which underpins the system, and investing roughly £1billion in the project.

EU member states are due to meet for a summit on Friday (November 25) to finalise the draft agreement.